Question is i have 2 01 350 blocks and need to find out their bore size. Also how far can i bore before these blocks are trash. Building a 302 z motor.:confused:

Question is i have 2 01 350 blocks and need to find out their bore size. Also how far can i bore before these blocks are trash. Building a 302 z motor.:confused:

350's have a 4.000 stock bore. You can go to .040 very safely. I have heard going as fas as .060, but that might be pushing it a little bit.

.060 is routine with these blocks, check with your machinist.

You can go to .040 very safely. I have heard going as fas as .060, but that might be pushing it a little bit.
60/1000 is fine for a very mild street or stock engine, I wouldnt go 60 for a track engine into 12s...well maybe if expect a season out of it...anything over is bonus

.060 is routine with these blocks, check with your machinist.
There is a lot of difference between a machinist and a good machinist with yrs of experiance under their belt....hence opinions do vary greatly.
Generally they will not garantee when taken out 60/1000....it is not they dont garantee their work at 60/1000 that doesnt cost much...its because if fails it also means cost of pistons crank everything...and not worth the risk for such a comeback.

The other issue is with walls thinner, on 1st fireup if it too lean and/or over advanced, the intail heat distrubution makes collapsing of piston skirts far greater.

You can get the block sonic tested which will help determine how much you can overbore the cylinders. Most 4 inch sbc blocks will go 60 over without any problem.